Error has made man so deep, sensitive, and inventive that he has put forth such blossoms as religions and arts. Pure knowledge could not have been capable of it.

The love of power is the demon of mankind.

Zarathustra was the first to consider the fight of good and evil the very wheel in the machinery of things: the transposition of morality into the metaphysical realm, as a force, cause, and end in itself, is his work. [...] Zarathustra created this most calamitous error, morality; consequently, he must also be the first to recognize it.

You want to be paid as well, you virtuous! You want reward for virtue, and heaven for earth, and eternity for your today?

In his heart every man knows quite well that, being unique, he will be in the world only once and that no imaginable chance will for a second time gather together into a unity so strangely variegated an assortment as he is: he knows it but hides it like a bad conscience.

When we talk in company we lose our unique tone of voice, and this leads us to make statements which in no way correspond to our real thoughts.

It is not conflict of opinions that has made history so violent but conflict of belief in opinions, that is to say conflict of convictions.